$ git clone -n https://src.fedoraproject.org/rpms/ghc-pretty-show.git /var/lib/mock/f40-build-2066445-49285/root/chroot_tmpdir/scmroot/ghc-pretty-show
Cloning into '/var/lib/mock/f40-build-2066445-49285/root/chroot_tmpdir/scmroot/ghc-pretty-show'...
$ git fetch origin 1fc6b4599c7f4a8da3d128f64ead8db841ec2c38:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-pretty-show
 * [new ref]         1fc6b4599c7f4a8da3d128f64ead8db841ec2c38 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1fc6b45 bump release